Electronic peripherals connect to terminals via a connection interface comprising electrical connector. A peripheral connector mates with a terminal connector to complete the electrical connection. Typically a pin connector is used for making the electrical connection from the peripheral to the terminal. The terminal connector may be, for example, one of either a pin connector or a socket connector which mates with a suitable connector on the peripheral thereby allowing for interface between the terminal and the peripheral.
Typically, power is constantly provided to the terminal connector so that when a peripheral is connected to the terminal, power is provided to the peripheral via the connection. When the peripheral is a powered device, i.e. does not require the power from the terminal to operate but is either independently powered or receives power from a supply other than the terminal, it is unnecessary to constantly provide power to the electrical connector on the terminal. However, if the peripheral is unpowered, as is becoming common, power to the peripheral must be supplied for the peripheral to operate. It is therefore typical to have an arrangement wherein power is constantly supplied to the electrical connection thereby allowing for either powered or unpowered peripherals to be connected.
A problem associated with such an arrangement is the de-plating (reverse electroplating) of the contacts of the terminal connector. The de-plating is due to an accumulation of a conductive solution across the contacts through which a current runs as a result of the constantly supplied voltage. The conductive solution may be for example sweat, condensation, rain, etc. This can damage the contacts or even destroy them. To avoid this problem, power to the connector must be turned off. However, turning off the voltage to the electrical connection means that the terminal cannot detect unpowered peripherals that are attached.
A further problem associated with having a terminal connector constantly powered is the danger associated with exposing the powered terminal connector to a hazardous environment wherein a spark caused, for example by connecting a peripheral, puts the user at risk. For example, the environment may contain flammable gas or material such as hydrogen, sawdust, high oxygen concentration, gasoline, etc. In such an environment, a user must remember to power down the terminal or the connector.
A need therefore exists to provide a device that allows for use of an unpowered peripheral while preventing the contacts from being de-plated.